“My roof is a bit overdue for a cleaning. After all, the ad says they won’t walk on my roof”.
So you call the number and schedule service. The service company shows up, but two out of three times, they don’t show up in the truck with the bucket you saw in the ad. Instead it’s a 250 pound service tech who is now climbing onto your tile roof. However, he tells you,
“Don’t worry, I’m only walking on the ridge, not the roof”.
Truth be told, there is almost no way that you can properly clean an entire roof from the inside of a bucket truck. There will almost always be places that you need to walk the roof to clean it properly.
This then leads to things like cracked roof tiles, roof damage and moreover a wet roof is dangerous; especially when dealing with slick tiles. Moreover, I am a professional roofer, and I am not sure how washing a roof will extend its lifetime. In fact, I will make a case that the opposite is true.
Decreasing the Lifetime of your Roof
Most pressure washer mixes are comprised of a combination of chemicals. Of these chemicals bleach is the most commonly used solvent. Bleach has a reaction when it comes into contact with the underlayment. Once the underlayment becomes compromised it’s only a matter of time before you have roof leaks.
So while having a clean roof may improve your home’s exterior appearance, just make sure you aren’t doing it at the cost of damaging your roof.
Article: Roof Cleaning, a Buyer Beware Tip
For additional information on why you shouldn't have your roof professionally cleaned: